The fabrication of ferromagnetic nanocontact structure

In this paper, we report the fabrication of permalloy nanocontact structures with greatly improved surface and edge smoothness. Magnetic sputtering and thermal evaporation were used for metal film deposition, and lift-off and dry etching techniques were employed for nanocontact structure patterning. The compositional properties of the resulting nanocontacts were investigated using energy dispersive analysis of X-ray (EDAX). Atom force microscope and scanning electron microscope were used for morphological characterisation. We found that high quality permalloy nanocontact structures can be obtained by using the combination of thermal evaporation and lift-off with optimised processing parameters; meanwhile, in the case of depositing metal films using magnetic sputtering, dry etching technique rather than lift-off was used for improved surface morphology of the nanostructures.